The YA fantasy genre has been turned on its head since October 28, when Netflix launched The Bastard Son & The Devil Himself, the Joe Barton-penned adaptation of Sally Green’s Half Bad trilogy. Executive produced by veteran actor/director Andy Serkis, the fast-paced new series is full of raw, powerful performances from a passionate cast… and plenty of gore.

Sixteen-year-old Nathan Byrne (Jay Lycurgo of Titans fame) is the illegitimate son of the world’s most dangerous Blood witch, dubbed ‘The Wolf’ and portrayed brilliantly by Interstellar’s David Gyasi.

Fearing he will follow in his father’s footsteps, Nathan is constantly monitored in the Fairborn witch world, labelled as the light in comparison to the Bloods’ darkness. But as the boundaries between ‘good’ and ‘bad’ fray, Nathan – along with mischievous Annalise (Nadia Parkes) and charismatic alchemist Gabriel (Emilien Vekemans) – will soon discover who he truly is. Making him miserable along the way is his vengeful half-sister Jessica (Isobel Jesper Jones make her ruthlessly cunning debut).

In eight epic episodes, which lure the viewer on a violence-filled rollercoaster of a journey through magic, sex and friendship, Nathan’s bloodline is only one facet of numerous compelling storylines from the mind behind The Lazarus Project and Giri/Haji. Oh, and Ireland’s own Róisín Murphy makes her film debut as Blood witch Mercury, Gabriel’s master and adoptive mother from whom Nathan seeks help. As he waits until his 17th birthday to receive his power, a string of events are unlocked that changes the world forever.

Róisín Murphy as Mercury in Netflix's 'The Bastard Son & The Devil Himself'.

“When we find Nathan at the start of the story, he’s incredibly isolated and lonely,” notes Lycurgo. “He lives in a caravan with his gran, who he loves deeply, and his sister, who hates him. He lost his mum to suicide when he was a child, which Jessica blames him for, and his dad is the most evil witch on the planet. There’s a huge weight on his shoulders, and it leaves him really confused. He’s a very cheeky, charming boy at times, but the story is ultimately about him working out who he truly is.”

Just as Nathan has Fairborn and Blood witch lineage, his character’s light-hearted wit also contrasts with the struggle to control his trauma, rage and pain. The more anger the Fairborn witches see, the more they assume he’ll follow in his Blood witch father’s footsteps.

“That’s Joe Barton’s writing,” Jay nods. “We were given something so dark and devastating but also light and humorous. That’s what really excited me about the script. As an actor, if your imagination starts going off when you’re reading lines, that’s a really good sign. I loved Nathan’s character. I’m quite fun as well, but I wanted to get wrapped up in someone human and raw. The challenges of playing every side of Nathan really excited me.

“He doesn’t want to be part of this massive war between both blood lineages in his life, seemingly caused by his evil biological father, who he’s never even met. Nathan just wants to be a normal kid. He’s fighting the blame constantly left at his feet. Annalise and Gabriel represent two different sides – Fairborns and Bloods – and he loves them both.”

The sardonic Gabriel’s entrance in episode three is a surefire audience-pleaser. Nathan and Annalise find their way to an apartment when seeking out Mercury for help, only to stumble into her adoptive son and helper, Gabriel, in his boxers and robe.

“When I first read the audition scene, I fell in love with Gabriel,” enthuses Vekemans. “He was really fun. As a French alchemist, he can make potions and powders with magic. He’s given a mission to bring Nathan to his master, Mercury, but ends up helping them in their quest to find Nathan’s blood. Gabriel is incredibly cynical, but there are things underlying that showing his weaknesses. I immediately wanted to play him for that reason.”

Emilien Vekemens as Gabriel in Netflix's 'The Bastard Son & The Devil Himself'.

“Episodes one and two are so serious, and then this charming man in a robe comes in,” Jay laughs, shaking his head. “That’s what everyone’s waiting for, the Gabriel apartment scene.”

“He’s very original,” Emilien grins.

“We saw the show’s posters for the first time in South Kensington,” Jay offers, trying to contain a laugh. “This guy [points at his co-star] is right next to a poster of Gabriel, and a massive group of girls just swarm him. It was scary because they didn’t even know the show! They just saw this chiselling man (laughs). That’s what they can expect.”

Gabriel also represents one aspect of the show’s queer storyline. As representation, his sexuality is a minor footnote naturally draped inside the dialogue and evolving dynamics.

“I didn’t really think about Gabriel being the ‘queer representation’ of the show, to be honest,” Emilien concedes. “I was really into finding his humour and playing with how sarcastic he is, and his Frenchness! That was more my goal.”

He shares one critical scene in particular with the aforementioned Murphy.

“That was a lot of fun,” Emilie reflects. “She really put the work in. We did some rehearsals before we properly met and then shot the scene at the end of the six months, so it was nice to see her before. Róisín was amazing. She brings a kind of seduction in the way she delivers the lines. To be honest, during our main scene, I just had to look at her and she did everything for me.

“I just responded to what she was giving. She was generous. It was her first experience. Obviously, she has been on many big stages and she wasn’t nervous. She was just at one with the character. Róisín’s got wonderful dresses as well!”

The chemistry between Gabriel, Nathan and Annalise is undeniably a highlight. Clearly, the casting director saw a spark ignite between trio, who became close on set.

“I met Nadia Parkes [Annalise] about two years before we even filmed,” explains Lycurgo . “We auditioned for this indie film, and I ended up getting it but she didn’t. It was four girls and then me against another guy. I remember thinking how incredible she was, so raw and powerful. She really cares about the craft. I met Emilien at the first table read, and we got close. You can see in the scene at Gabriel’s apartment how lovely the chemistry is. That was the first time we got to work together and really play around as a group. We knew it was going to be a great time from then. Especially in those emotional scenes, we respected each other and collaborated.”

Nadia Parkes and Jay Lycurgo as Annalise and Nathan in in Netflix's 'The Bastard Son & The Devil Himself'.

“We stayed at the same place during the whole shooting process, which was nice,” adds Vekemans. “We could chat about the scenes and – ”

“Not party!”interjects Jay.

“Work!” Emiliens laughs. “So hard.”

All four cast members insist that The Bastard Son… stands out from the YA competition.

“I’ve seen a lot of comments on the trailer saying it’s just another fantasy YA show, but you’re not even ready!” says Jay passionately. “These characters are so real. We really went for it in every single scene.”

“We tried to find the rawness in a very natural way,” agrees Emiliens. “We would try to really showcase the human bonds behind the magic. That was the tone we were looking for from an acting point of view.”

“Everyone feels so real and complex,” says Nadia Parkes. Annalise plays the role of Nathan’s primary love interest, but her newfound power twists her path forward. “It’s just an absolute treat to be able to work on Joe’s dialogue and within the world he created so fully.”

“The humour stood out for me,” says Isobel says, though Jessica has to deliver some of the most ruthless lines. “I love that cutting, sarcastic, non-referential comedy. I don’t think you get that all the time in fantasy. It’s gritty. I’ll never forget reading through the episodes for my callback and I was trying to make notes about Jessica. I totally forgot I was doing a job, I was so taken in by the plot. The journey you’re taken on is mad.”

Isobel Jesper Jones as Jessica in Netflix's 'The Bastard Son & The Devil Himself'.

“I got the call from my agent and cried for maybe three days straight, consistently,” Nadia recalls of the moment she was confirmed as Annalise. “I got really drunk to celebrate!”

“The waiting process was so excruciating,” Isobel jumps in. “My agent called me and I was declogging my bath. It’s really gross, but that’s what I was doing! On my photo roll, it’s me sending a photo of my flatmates like, ‘We need to sort the bath out’, and the next photo is a screenshot of a text from my agent saying, ‘You did it’. It was amazing.”

As a professional debut goes, playing the sadistic Jessica must have been a challenge.

“It’s a testament to the writing that there’s a character who claims to be so moral, but is so the other way,” says Jesper-Jones. “I was so excited to play her, because Jessica is incredibly complicated. At the beginning, you think, ‘Maybe it’s just a sibling rivalry between them’, but then you realise how cruel she really is. I loved getting to excavate some of the layers around that. There’s a lot of pain and damage in her life. The way she buries that and how it expresses itself is an actor’s dream. That being said, it was pretty horrible being on set and everyone was terrified of me!”

“But then they learned that she’s the nicest person in the world,” Nadia smiles.

“People would literally move out of the way when I was like, ‘Guys, does anyone want to have lunch?’” grins Isobel.

Both Nadia and Izzy got to work closely with Paul Ready, who plays Soul O’Brien, father of Annalise and commander of cadet hunter Jessica. He’s also a member of the Fairborn Council, but has a bone to pick (to say the least) with Nathan’s father, the Wolf.

“Paul blows my mind as an actor,” Nadia gushes. “I’m really in awe of him. We both learned so much from him and got private moments with him. Watching him create such a powerful, grounded performance for a truly mad evolution was amazing.”

“Oh my gosh, when I heard he was playing Soul, I freaked out,” Isobel exclaims. “There’s a Channel 4 series called Utopia, where he played a really dark character. It was like meeting a hero. Soul and Jessica’s relationship as the series goes on gets very complicated. There are so many very subtle strings to how their connection shifts, between a sort of father daughter dynamic, but straying elsewhere sometimes. I wouldn’t want to do that with anyone other than Paul. We had some really in-depth chats about the nature of darkness and evil. He’s lovely!”

Paul Ready as Soul O'Brien in Netflix's 'The Bastard Son & The Devil Himself'.

Jay Lycurgo also worked closely with Irish actor Karen Connell (Vikings), who plays the role of Ceelia, the badass Fairborn witch training him to fulfil the prophecy to kill his father.

“There’s a bit where Nathan has run 10 miles, and then Ceelia slaps him in the face when he finishes,” the 24-year-old Londoner grins. “Karen obviously didn’t do it properly (laughs), but Ceelia says, ‘What are your weaknesses? You’re tired and you’re not concentrating. What are mine?’ and Nathan says, ‘Underestimating me’, before picking her up and throwing her on the ground.

“I broke down crying because I had been doing non stop press-ups, running – everything Nathan had to go through. There was something lovely about that, but it got to the end of the week and I just fell apart after that scene. It was incredible, but really tough. We literally went through blood, sweat and tears for this show, I really mean that.”

“I love the physicality of the role,” Nadia jumps in. “I built up my fitness on that series. Before they’d say ‘Action’, I’d be squatting in the corner to try to get myself out of breath every time. Everyone has this image of me doing star jumps or squatting before every take!”

Will the madness continue for another season?

“I would love for it to carry on,” Jay replies. “It’s rare that you get these worlds with so much potential. That’s what’s so fun. We’ve only told a tiny bit of these guys’ stories and where it could go, but I can’t say what would happen without spoiling it!”

“It’s a fantasy show that we’ve never really seen before, because of its ability to be so grounded in reality,” says Nadia. “It’s one of a kind because of the creatives involved. My castmates are some of the most talented people I’ve ever worked with.”

• The Bastard Son & The Devil Himself is streaming on Netflix now.

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